Wireless electronic devices such as cellular phones, smart phones, a variety of portable/personal computing devices (e.g., personal digital assistants or “PDAs”), electronic book readers, video game consoles, and the like have become ubiquitous globally as a direct result of important advances in integrated circuit (ICs) designs and packaging of these ICs with increasing spatial densities. Communication towers, which populate most urban centers, typically communicate with wireless devices during data and voice transmission. Consequently, wireless devices serve as a focal point of contact with the towers, as they constantly receive and emit wireless signals carrying data. The wireless signals carrying data are transmitted as radio waves over a narrow band of frequencies. The presence of these signals can be detected by other devices in close proximity (e.g., at a distance from approximately 0.1 cm to 3 cm).
Cellular phone accessory manufacturers have exploited the ability to sense radio waves at close proximities so as to create appealing visual cues when a cellular phone receives an incoming call. For example, various components of the cellular phone itself can be made to flash brightly with different colors and time sequences in response to an incoming call. In particular, in some conventional implementations, the cellular phone may be configured such that one or more of the battery, antenna, or keyboard of the cellular phone are equipped with light-generating components that may be responsive to wireless signals representing incoming calls. Accessories such as key-chains and pens also are available with similar capabilities (i.e., light-generation in response to wireless signals in close proximity representing incoming calls to cellular phones; see e.g. www.cell-phone-accessories.com, www.cellphone-antenna-hologram.com, www.1st-cellphone-accessories.com).